A massive landslide occurred in Jure Village (Sindhupalchowk district) on the border between Mankha VDC-01 and Ramche VDC-04 at around 02.30am, local time on Saturday, 2 August 2014. The landslide blocked Sunkoshi River creating a high dam about 55 m across the river. Since, the dam was composed of shattered rock mass (detached blocks and boulders containing phyllite and quartzite) covered by cohesive material, the river water could not erode the landslide dam’s material. Subsequently the restricted flow formed into a natural lake, pooling about 3.5 Km stretch upstream.
The Sunkoshi landslide caused a large number of human fatalities, burial of human settlement, damages to infrastructures (including the complete obstruction of about 7 km of the Araniko Highway), and the complete submergence of SSHP as well as the Transmission line of other hydropower projects (including Sunkoshi Hydropower Project). The incident posed a threat to the supply of regular consumable goods, and also put a risk to the lives of sick and/or injured people requiring special medical attention from the worst affected area, and also resulted in a huge loss on the economy of the country.
The landslide-dam caused stoppage of generation from seven hydropower projects in the vicinity of slides. Power transmission from five hydropower projects—Bhotekoshi (45MW), Sunkoshi (10MW), SSHP (2.5MW), Chaku (6MW) and Bhairabkunda (3MW) were halted temporarily. A total of 66.5 MW of electricity had to be deducted from the national grid, increasing the power crisis of Nepal.
SSHP was the most affected hydropower project. The back flow water entered Sanima Hydropower Station at about 8:05 am and fully sub-merged the powerhouse by about 2:30 pm for a period of 36 days. The water level was maintained at about 840 amsl. Since, the powerhouse area lies at the sediment deposition zone, the powerhouse was covered by silt and fine sand.